The trophic preferences and ontogenic variations were evaluated and compared between five species of mojarras collected bimonthly for two years (2004-2005) in the hyperhaline lagoon system of Ría Lagartos, Yucatan Peninsula. A total of 361 specimens corresponding to Eucinostomus argenteus, Eucinostomus gula, Eucinostomus harengulus, Eugerres plumieri and Diapterus auratus were collected and used for trophic analysis. The trophic components were analyzed using the Relative Importance Index (RII) and multivariate analysis. The mojarras were defined as second-order consumers, feeding on microcrustaceans (amphipods, copepods, tanaidaceous, ostracods) and significant amounts of detritus with variations in the proportion and frequency of different types of food according to their ontogeny and food availability. Three species shared the same resources. However, differences were observed at the general and ontogenetic level, avoiding inter and intraspecific competition. Results provide evidence of the importance of these coastal habitats for the trophic requirements of marine-euryhaline juvenile fish species.The aim of this study was to evaluate and compare trophic preferences among five mojarras species collected bimonthly during two years (2004-2005) in the hyperhaline lagoon system of Ría Lagartos, Yucatan Peninsula. A total of 361 specimens corresponding to Eucinostomus argenteus, Eucinostomus gula, Eucinostomus harengulus, Eugerres plumieri and Diapterus auratus were collected and used for trophic analysis. The trophic components were analyzed by means of the Relative Importance Index (RII) and multivariate analysis. The mojarras were defined as second-order consumers, feeding on microcrustaceans (amphipods, copepods, tanaidaceans, ostracods) and significant amounts of detritus with variations in the proportion and frequency of different types of food according to their ontogeny and food availability. Considering food preferences three species shared the same resources. However, differences were observed at generally and ontogenetic level, avoiding inter and intraspecific competition. Results provide evidence of the importance of these coastal habitats for the trophic requirements of marine-eurihaline juvenile fish species.